General Motors Corporation invented a continuous collision severity prediction system which uses electronic front sensors (front-end accelerometers) to trigger severity calculation. Thereafter, it calculates the severity level using the sensing and diagnostic module. In fact, the use of electronic front sensors is not able to detect situations such as rolling over, and sudden slowdown.
Moreover, Takata Corporations developed a vehicle collision detecting system which includes an impact sensor for collision detection, and a distance sensor to detect any unavoidable collision by differentiating the distance. If a collision is detected or unavoidable, the airbag will be inflated. Nevertheless, it only focuses on head-on collisions without analyzing the severity levels of collision.
Furthermore, Sensor Technology Co. Ltd. developed a collision detection device which detects a collision by two one-axis acceleration sensors. It can also categorize the signals into different components and select different passenger safety devices. However, it can still not classify sudden slowdown, rolling over, etc.
In 1998, Daewoo Electronics Co. Ltd developed a method for judging a collision by using three directional accelerative signals. It analyzes the relationship of velocity with respect to time in three different axels and classifies 8 mph front barrier collision, 14 mph oblique collision and 16 mph center pole collision. However, it is not able to detect rolling over and sudden braking.
In 2002, At Road, Inc. presented a method and system for detecting vehicle collision using global positioning system. Abnormal deceleration is detected by second order differentiating the position signal from GPS. It assumes that such deceleration is only caused by external force such as collision. Motorola, Inc. designed a mobile phone to detect collision of a vehicle in 2006. It is able to transmit the collision signal through a mobile phone network. Although the prior inventions are developed for the detection of vehicles collision, they are not able to classify different severity levels such as rolling over, airbag activation, slight bumping, and sudden slowdown.
Obviously, the major problem of existing inventions is the failure of categorizing the severity level of a collision. With this capability, a traffic control center can make the decision on what resource should be used promptly. For instances, if it is just a slight bumping, maybe only traffic policy will be enough, and the most important need will be to ask the drivers drive their vehicles aside of the road for the recovering of traffic. If the airbag is activated or there is rolling over, ambulance should be called automatically and promptly to save the injured.